Abstract:

A method of removing contaminates from sour water is provided. The method
includes producing raw sour water within a syngas production system, and
removing the contaminates from the raw sour water using a chemical
reaction within a treatment unit to produce treated sour water. The
treatment unit is in flow communication with the syngas production
system.

Claims:

1. A method of removing contaminates from sour water, said method
comprising:producing raw sour water within a syngas production system;
andremoving the contaminates from the raw sour water via a chemical
reaction within a treatment unit to produce treated sour water, wherein
the treatment unit is coupled in flow communication with the syngas
production system.

2. A method in accordance with claim 1 further comprising stripping
ammonia from the raw sour water prior to removing the contaminates from
the raw sour water.

3. A method in accordance with claim 1 wherein removing contaminates from
the raw sour water further comprises:producing ozonated air;channeling
the ozonated air to a ozone contactor;channeling the raw sour water to
the ozone contactor; andreacting the raw sour water with the ozonated air
to remove the contaminates from the raw sour water to produce the treated
sour water and a gas.

4. A method in accordance with claim 1 further comprising:channeling the
treated sour water to at least one of a recycled solids tank, a grinding
mill, and a syngas scrubber; andchanneling the gas to a vent treatment
unit.

5. A method in accordance with claim 1 wherein removing contaminates from
the raw sour water further comprises:generating ultraviolet (UV)
light;transmitting the UV light to a UV contactor;channeling the raw sour
water to the UV contactor; andreacting the raw sour water with the UV
light to remove the contaminates from the raw sour water to produce the
treated sour water.

6. A method in accordance with claim 1 wherein removing contaminates from
the raw sour water further comprises:channeling a metered amount of
hydrogen peroxide to a reaction chamber;channeling the raw sour water to
the reaction chamber; andreacting the raw sour water with the hydrogen
peroxide to remove the contaminates from the raw sour water to produce
the treated sour water.

7. A method in accordance with claim 1 further comprising channeling the
treated sour water to at least one of a recycled solids tank, a grinding
mill, and a syngas scrubber.

8. A sour water treating system comprising:a condensate stripper
configured to produce raw sour water;a condensate stripper cooler coupled
in flow communication with said condensate stripper, said condensate
stripper cooler configured to receive the raw sour water from said
condensate stripper;an outlet line configured to channel the raw sour
water from said condensate stripper cooler; anda treatment unit coupled
in flow communication between said condensate stripper cooler and said
outlet line, said treatment unit configured to substantially remove
contaminates from the raw sour water via a chemical reaction.

9. A sour water treating system in accordance with claim 8 wherein said
outlet line channels the raw sour water from said condensate stripper
cooler to at least one of a storage tank and a syngas scrubber.

10. A sour water treating system in accordance with claim 8 wherein said
treatment unit comprises an ozone contactor configured to react the raw
sour water and ozonated air to substantially remove the contaminates from
the raw sour water.

11. A sour water treating system in accordance with claim 10 wherein said
treatment unit further comprises an ozone generator configured to produce
the ozonated air from air.

12. A sour water treating system in accordance with claim 8 wherein said
treatment unit comprises an ultraviolet (UV) contactor configured to
react the raw sour water with UV light to substantially remove the
contaminates from the raw sour water.

13. A sour water treating system in accordance with claim 12 wherein said
treatment unit further comprises a UV light generator configured to
generate the UV light, said UV contactor comprises:at least UV light tube
optically coupled to said UV light generator such that the UV light is
transmitted through said at least one UV light tube; andat least one sour
water tube coupled proximate to said at least one UV light tube such that
the raw sour water and the UV light react to substantially remove the
contaminates from the raw sour water.

14. A sour water treating system in accordance with claim 8 wherein said
treatment unit comprises a hydrogen peroxide contactor configured to
react the raw sour water with hydrogen peroxide to substantially remove
the contaminates from the raw sour water.

15. A sour water treating system in accordance with claim 14 wherein said
treatment unit further comprises a metering pump configured to meter a
predetermined amount of the hydrogen peroxide to said hydrogen peroxide
contactor.

16. A syngas generation system comprising:a gasifier configured to produce
syngas and at least one by-product;a condensate stripper configured to
produce raw sour water from the at least one by-product;a condensate
stripper cooler coupled in flow communication with said condensate
stripper, said condensate stripper cooler configured to receive the raw
sour water from said condensate stripper;a liquid outlet line configured
to channel the raw sour water from said condensate stripper cooler; anda
treatment unit coupled in flow communication between said condensate
stripper cooler and said liquid outlet line, said treatment unit
configured to substantially remove contaminates from the raw sour water
via a chemical reaction.

17. A syngas generation system in accordance with claim 16 wherein said
treatment unit comprises:an ozone generator configured to produce the
ozonated air from air; andan ozone contactor configured to react the raw
sour water and the ozonated air to substantially remove the contaminates
from the raw sour water.

18. A syngas generation system in accordance with claim 16 wherein said
treatment unit comprises:an ultraviolet (UV) light generator configured
to generate UV light; anda UV contactor comprising:at least UV light tube
optically coupled to said UV light generator such that the UV light is
transmitted through said at least one UV light tube; andat least one sour
water tube coupled proximate to said at least one UV light tube such that
the raw sour water and the UV light react to substantially remove the
contaminates from the raw sour water.

19. A syngas generation system in accordance with claim 16 wherein said
treatment unit comprisesa hydrogen peroxide contactor configured to react
the raw sour water with hydrogen peroxide to substantially remove the
contaminates from the raw sour water; anda metering pump configured to
meter a predetermined amount of the hydrogen peroxide into said hydrogen
peroxide contactor.

20. A syngas generation system in accordance with claim 16 further
comprising at least one of a recycled solids tank, a grinding mill, a
syngas scrubber, and a vent treatment unit configured to receive at least
one product produced within said treatment unit.

Description:

BACKGROUND OF THE INVENTION

[0001]The embodiments described herein relate generally to methods and
system for treating sour water and, more particularly, to methods and
system for use in removing contaminates from sour water.

[0002]At least some known systems, such as gasification systems, produce
sour water. As used herein, the term "sour water" refers to water that
includes cyanide, hydrocarbons, hydrogen sulfide, ammonia, phenol,
selenium, salts, organics, and/or other chemicals. Further, as used
herein, the term "cyanide" refers to any chemical compound that includes
a carbon atom bonded to a nitrogen atom (CN), such as simple cyanides
and/or cyano complexes, the term "ammonia" refers to any chemical
compound that includes NH3 and/or NH4OH, and the term
"organics" refers to any chemical compound that includes carbon (C).
Further, as used herein, the term "contaminates" refers to cyanide,
ammonia, and/or organics.

[0003]In at least one known gasification system, a low temperature gas
cooling section produces sour water in the form of recovered process
condensate. A condensate ammonia stripper removes ammonia, hydrogen
sulfide (H2S) and/or other trace components from the recovered
process condensate to produce stripped sour water. Cyanide from the
stripped sour water may become concentrated in an overhead reflux stream
within a column downstream from the condensate ammonia stripper. In such
a system, a small blowdown stream, i.e., approximately 1-10 gallons per
minute (gpm), of sour water is routed from the reflux stream to a recycle
solids tank for use in preventing cyanide from concentrating in the
column and/or overhead piping. Without the blowdown stream, high
metallurgy materials may be required in a reflux pump suction, a reflux
pump, an overhead condenser, and/or condenser return piping to the
overhead condenser. When routed to the recycled solids tank and/or pumped
to a grinding mill, cyanide from the blowdown stream can potentially
create exposure hazards.

[0004]As such, it is desirable to remove contaminates from sour water
before the sour water is channeled to a recycle solids tank and/or a
grinding mill. More particularly, it is desirable to remove contaminates
from sour water streams produced in an ammonia stripping system of a
gasification system.

BRIEF DESCRIPTION OF THE INVENTION

[0005]In one aspect, a method of removing contaminates from sour water is
provided. The method includes producing raw sour water within a syngas
production system, and removing the contaminates from the raw sour water
via a chemical reaction within a treatment unit to produce treated sour
water. The treatment unit is coupled in flow communication with the
syngas production system.

[0006]In another aspect, a sour water treating system is provided. The
sour water treating system includes a condensate stripper configured to
produce raw sour water and a condensate stripper cooler coupled in flow
communication with the condensate stripper. The condensate stripper
cooler is configured to receive the raw sour water from the condensate
stripper. The system further includes an outlet line configured to
channel the raw sour water from the condensate stripper cooler and a
treatment unit coupled in flow communication between the condensate
stripper cooler and the liquid outlet line. The treatment unit is
configured to substantially remove contaminates from the raw sour water
via a chemical reaction.

[0007]In yet another aspect, a syngas generation system is provided. The
syngas generation system includes a gasifier configured to produce syngas
and at least one by-product, a condensate stripper configured to produce
raw sour water from the at least one by-product, and a condensate
stripper cooler coupled in flow communication with the condensate
stripper. The condensate stripper cooler configured to receive the raw
sour water from the condensate stripper. The syngas generation system
further includes a liquid outlet line configured to channel the raw sour
water from the condensate stripper cooler, and a treatment unit coupled
in flow communication between the condensate stripper cooler and the
liquid outlet line. The treatment unit is configured to substantially
remove contaminates from the raw sour water via a chemical reaction.

[0008]By including a treatment unit configured to remove contaminates from
sour water produced by a condensate ammonia stripper, the embodiments
herein facilitate removing contaminates from the sour water before the
sour water is further processed in, for example, a recycled solids tank
and/or a grinding mill. As such, the methods and systems described herein
facilitate reducing potential hazard from contaminates exposure.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009]FIGS. 1-6 show exemplary embodiments of the systems and methods
described herein.

[0010]FIG. 1 is a schematic illustration of an exemplary syngas generation
system.

[0011]FIG. 2 is a schematic view of an exemplary condensate stripper that
may be used with the syngas generation system shown in FIG. 1.

[0012]FIG. 3 is a schematic view of an exemplary condensate stripper
cooler that may be used with the syngas generation system shown in FIG.
1.

[0013]FIG. 4 is a schematic illustration of an exemplary treatment unit
that may be used with the gasification for syngas generation system shown
in FIG. 1.

[0014]FIG. 5 is a schematic illustration of an alternative exemplary
treatment unit that may be used with the gasification for syngas
generation system shown in FIG. 1.

[0015]FIG. 6 is a schematic illustration of another alternative exemplary
treatment unit that may be used with the gasification for syngas
generation system shown in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

[0016]The exemplary embodiments described herein provide methods and
systems for removing contaminates from a sour water stream within a
gasification system. In one embodiment, ozone is used to oxidize cyanide
and/or other contaminates into safe oxidation by-products. In an
alternative embodiment, ultraviolet light is used to react cyanide and/or
other contaminates into safe by-products. In another alternative
embodiment, hydrogen peroxide is used to oxidize cyanide and/or other
contaminates into safe oxidation by-products. As such, the embodiments
described herein facilitate preventing contaminates from accumulating in
a condensate ammonia stripper and/or removing contaminates from a recycle
solids tank and/or grinding area.

[0017]FIG. 1 is a schematic diagram of an exemplary gasification for
syngas generation system 10. FIG. 2 is a schematic view of an exemplary
condensate stripper 70 that may be used with syngas generation system 10.
FIG. 3 is a schematic view of an exemplary condensate stripper cooler 90
that may be used with syngas generation system 10.

[0018]In the exemplary embodiment, syngas generation system 10 includes an
air separation unit (ASU) 12 for use in separating air 14 to produce
gasifier oxygen 16 and a carbonaceous fuel preparation unit 18 for
preparing carbonaceous fuel 20 and water 22 to produce gasifier fuel 24.
ASU 12 and fuel preparation unit 18 are coupled in flow communication to
a gasifier 26 that produces a gas/solids mixture 28 by a partial
oxidation process of gasifier oxygen 16 and fuel 24. Mixture 28 includes
the main product synthetic gas ("syngas") and at least one by-product,
which may include slag and unburned carbon, condensate, solids, liquids,
and/or gases. Gasifier 26 is coupled in flow communication to a syngas
cooler 30 that facilitates cooling mixture 28 to a cooled gas/solids
mixture 32. Boiler feed water 34 is fed into syngas cooler 30 to produce
steam 36 for use in downstream units. Syngas cooler 30 is coupled in flow
communication to a gas/liquid/solids separation apparatus 38 wherein the
cooled gas/solids mixture 32 is separated into raw syngas 40 (gas), black
water 42 (liquid), and slag 44 (solids). Slag 44 is a by-product that may
be reused and/or disposed of off-site.

[0019]Black water 42 from gas/liquid/solids separation apparatus 38 is
channeled to a black water handling unit 46. Black water handling unit 46
separates black water 42 into grey water 48 for processing in grey water
handling unit 50 and a stream 52 having a high concentration of suspended
solids, wherein the stream 52 can be reused in fuel preparation unit 18.
Grey water handling unit 50 processes grey water 48 to produce a
relatively lower suspended solids grey water 54 for use in a syngas
scrubber 64 and a relatively higher suspended solids grey water 56 as
wastewater. Grey water 54, which has less suspended solids as compared to
black water 42 or grey water 48 and/or 56, may be combined with makeup
water 58, if needed, and, in the exemplary embodiment, is used in syngas
scrubber 64 as a scrubbing water for the raw syngas 40. A portion of grey
water 48 is discharged as wastewater or grey water blowdown 56 to a
wastewater processing system 60 to facilitate reducing contaminant
buildup that may adversely affect syngas generation system 10.

[0020]Raw syngas 40 is converted to clean syngas 62 by processing raw
syngas 40 serial through a syngas scrubber 64, a syngas cooling system
66, and an acid gas removal system 68. More specifically, syngas scrubber
64 scrubs particulates from raw syngas 40 to produce scrubbed syngas 70
and produces water 72 for use in gas/liquid/solids separation apparatus
38. Syngas cooling system 66 facilitates cooling the scrubbed syngas 70
to produce low temperature syngas 74 that is channeled to acid gas
removal system 68 and to produce condensate 76 and 78 for use in
processing within a condensate stripper 80 and gas/liquid/solids
separation apparatus 38, respectively. Condensate 76, in the exemplary
embodiment, is raw sour water. Acid gas removal system 68 removes acid
gas 82 from low temperature syngas 74 to produce clean syngas 62. Acid
gas 82 is a by-product that may be processed and/or disposed of in
downstream units. Clean syngas 62 is the main product of syngas
generation system 10 and can be used for power production, chemical
production, and/or other usage. Gasifier 26, syngas cooler 30, separation
apparatus 38, a syngas scrubber 64, a syngas cooling system 66, and an
acid gas removal system 68 are also referred to herein as a syngas
production system 69. As such, syngas production system 69 produces at
least syngas 62 and sour water 76.

[0021]In the exemplary embodiment, condensate stripper 80 strips ammonia
from sour water 76 to produce stripped condensate or stripped sour water
84, a by-product ammonia gas or sour gas 86, and stripper bottoms 88.
Sour gas 86 may be processed and/or disposed of in downstream units.
Stripper bottoms 88 is routed to separation apparatus 38 for further
processing. Stripped sour water 84 is routed from condensate stripper 80
to a condensate stripper cooler 90 for cooling thereof. Condensate
stripper cooler 90 cools stripped sour water 84 and separates stripped
sour water 84 into stripped sour water 92 and a recirculation stream 94.
Sour water 92 that is discharged from condensate stripper cooler 90 is
chemically similarly to sour water 84 channeled into condensate stripper
cooler 90 but has a lower temperature than sour water 84. As such, sour
water 92 is also referred to as cooler sour water.

[0022]Recirculation stream 94 is condensed vapor in a liquid state that is
used as water in syngas generation system 10 and/or exits through an
overhead condenser. Stripped sour water 92 is channeled to a treatment
unit 96 to facilitate removal of compounds, such as contaminates, from
stripped sour water 92, as described in more detail below. In the
exemplary embodiment, treatment unit 96 is considered to be part of a
condensate ammonia stripper overhead reflux loop. Treated sour water 98
is discharged from treatment unit 96 to any suitable location, such as a
recycled solids tank 100. Additionally, or alternatively, treated sour
water 98 is discharged to syngas scrubber 64. Any gases 102 produced
during treatment of stripped sour water 92 within treatment unit 96 are
discharged to any suitable location, such as a vent treatment unit 104.
Vent treatment unit 104 is, for example, a sulfur recovery unit, a
sulfuric acid plant, a thermal oxidizer, and/or any other suitable type
of treatment device. In the exemplary embodiment, condensate stripper 80,
condensate stripper cooler 90, and treatment unit 96 form a stripping and
treating system within syngas generation system 10.

[0023]A control system 106 is coupled in operational control communication
with syngas generation system 10 to control the components therein to
form syngas 62. As used herein, the term "operational control
communication" refers to a link, such as a conductor, a wire, and/or a
data link, between two or more components of syngas generation system 10
that enables signals, electric currents, and/or commands to be
communicated between the two or more components. The link is configured
to enable one component to control an operation of another component of
syngas generation system 10 using the communicated signals, electric
currents, and/or commands.

[0024]FIG. 4 is a schematic illustration of an exemplary treatment unit
200 that may be used with syngas generation system 10 (shown in FIG. 1)
as treatment unit 96 (shown in FIGS. 1-3). Treatment unit 200 includes an
ozone generator 202, an ozone contactor 204, a backpressure control
circuit 206, and a bypass circuit 208. Ozone generator 202 is coupled in
flow communication with ozone contactor 204 via a pump 210. Although a
pump is described herein, it should be understood that pump 210 can be a
compressor, a blower, and/or any other suitable flow control device. In
the exemplary embodiment, backpressure control circuit 206 is coupled in
flow communication between ozone contactor 204 and vent treatment unit
104. Bypass circuit 208 is coupled in flow communication between ozone
contactor 204 and recycled solids tank 100 and/or condensate stripper 80.
In the exemplary embodiment, ozone contactor 204 acts as a flash drum.

[0025]In the exemplary embodiment, air 212 and an electrical discharge 214
are supplied to ozone generator 202. Air 212 can be supplied to ozone
generator 202 from the atmosphere, from within syngas generation system
10, and/or from any suitable source. The flow of air 212 is controlled
using a valve 216, such as a hand valve. Within ozone generator 202,
electrical discharge 214 at least partially electrically breaks down air
212 to generate ozonated air 218. As such, electrical discharge 214 is of
a sufficient voltage to ionize air 212 to produce ozonated air 218 from
air 212. Alternatively, ozonated air 218 is generated within ozone
generator 202 from the electrolysis of water. In the exemplary
embodiment, ozonated air 218 is drawn from ozone generator 202 by pump
210.

[0026]Ozone contactor 204 includes, in the exemplary embodiment, a shell
220 that encloses a sour water inlet tube 222, a reaction chamber 224,
and an ozonated air injector 226. Sour water inlet tube 222 is coupled in
flow communication with condensate stripper cooler 90 and, in the
exemplary embodiment, extends along a longitudinal axis 228 of ozone
contactor 204. Reaction chamber 224 is defined between sour water inlet
tube 222 and shell 220. Ozonated air injector 226 is positioned within
reaction chamber 224 and includes at least one injector nozzle 230. In
the exemplary embodiment, ozonated air injector 226 includes an annular
manifold 232 that is coupled in flow communication with ozone generator
202 via pump 210. Annular manifold 232 extends through reaction chamber
224 about sour water inlet tube 222 and includes a plurality of injector
nozzles 230. Alternatively, ozonated air 218 and stripped sour water 92
can be introduced and/or reacted within ozone contactor 204 by any
suitable technique and/or method that enables treatment unit 200 to
function as described herein. In the exemplary embodiment, ozone
contactor 204 has a residence time that is sufficient to oxidize
containments present in stripped sour water 92.

[0028]Bypass circuit 208 is positioned along liquid outlet line 240 and
includes, in the exemplary embodiment, a plurality of valves 244, a level
transmitter 246, a high/low alarm 248, and a level controller 250. More
specifically, at least one valve 244 is coupled to liquid outlet line
240. Level controller 250 is in operational control communication with at
least one valve 244, and is electrically coupled to level transmitter 246
and high/low alarm 248 for receiving data from level transmitter 246
and/or high/low alarm 248. Alternatively, bypass circuit 208 may have any
suitable configuration that enables components of treatment unit 200 to
be controlled for performing maintenance, level control operations,
and/or other operations of treatment unit 200. In the exemplary
embodiment, level transmitter 246 senses a level of sour water 92 within
ozone contactor 204, and high/low alarm 248 determines whether the sensed
level satisfies predetermined conditions. If, for example, the sensed
level is above a predetermined threshold, bypass circuit 208 reduces a
level within ozone contactor to satisfy the predetermined conditions. In
the exemplary embodiment, bypass circuit 208 is self-draining.

[0029]Backpressure control circuit 206 is positioned along gas outlet line
242 and includes a plurality of valves 252, a pressure transmitter 254,
and a pressure controller 256. More specifically, at least one valve 252
is coupled to gas outlet line 242. Pressure controller 256 is in
operational control communication with at least one valve 252, and is
electrically coupled to pressure transmitter 254 to receive data from
pressure transmitter 254. Alternatively, backpressure control circuit 206
has any suitable configuration that enables components of treatment unit
200 for performing pressure control operations and/or other operations of
treatment unit 200. In the exemplary embodiment, pressure transmitter 254
senses a pressure within gas outlet line 242 and transmits the sensed
pressure to pressure controller 256. Pressure controller 256 controls at
least one valve 252 to control the pressure within gas outlet line 242.
In the exemplary embodiment, backpressure control circuit 206 is
self-draining.

[0030]Control system 106 is in operational control communication with at
least an inlet valve 258, ozone generator 202, pump 210, valve 216,
bypass circuit 208, and backpressure control circuit 206 for controlling
components of treatment unit 200 to function as described herein. During
a treatment operation, stripped sour water 92 enters ozone contactor 204
from ammonia stripper 90 when inlet valve 258 is opened. Further,
ozonated air 218 is produced from air 212 and electrical discharge 214 is
produced from ozone generator 202 when valve 216 is opened. Pump 210
channels ozonated air 218 from ozone generator 202 to ozone contactor
204. More specifically, control system 106 controls an amount of ozonated
air 218 and an amount of stripped sour water 92 entering ozone contactor
204 based on reaction criteria, such as a predetermined stoichiometric
ratio within ozone contactor 204. For example, a super-stoichiometric
amount of air 212 is routed to ozone generator 102 to produce ozonated
air 218.

[0031]Stripped sour water 92 enters ozone contactor 204 through inlet tube
222 and flows into reaction chamber 224. Ozonated air 218 is discharged
into reaction chamber 224 of ozone contactor 204 through at least one
nozzle 230. In the exemplary embodiment, when ozonated air 218 contacts
stripped sour water 92, a resulting chemical reaction substantially
removes contaminates from stripped sour water 92 to produce treated sour
water 98. In one embodiment, ozonated air 218 is channeled to ozone
contactor 204 and saturates stripped sour water 92 with
super-stoichiometric amounts of ozone to oxidize stripped sour water 92.
In the exemplary embodiment, ozone contactor 204 is designed with
sufficient residence time to ensure substantially all of the contaminates
within stripped sour water 92 is reacted with the ozone to produce
treated sour water 98.

[0032]Waste gas 102 is channeled from ozone contactor 204 through gas
outlet line 242 to vent treatment unit 104 for further processing.
Backpressure control circuit 206 controls a pressure of gas 102 within
gas outlet line 242. Treated sour water 98 is channeled from ozone
contactor 204 through liquid outlet line 240 to recycled solids tank 100.
Alternatively or additionally, treated sour water 98 is channeled from
ozone contactor 204 to condensate stripper 80, which facilitates
preventing contaminates from accumulating in condensate stripper 80
and/or removing contaminates from recycled solids tank 100 and/or a
grinding area. In the exemplary embodiment, bypass circuit 208 controls a
flow of treated sour water 98 through liquid outlet line 240.

[0033]FIG. 5 is a schematic illustration of an exemplary treatment unit
300 that may be used with syngas generation system 10 (shown in FIG. 1)
as treatment unit 96 (shown in FIGS. 1-3). In the exemplary embodiment,
treatment unit 300 includes an ultraviolet (UV) light generator 302 and a
UV contactor 304. UV light generator 302 produces UV light 306.

[0034]In the exemplary embodiment, UV contactor 304 includes at least one
UV light tube 308 and at least one sour water tube 310 that is proximate
to UV light tube 308. UV light generator 302 is optically coupled to UV
light tube 308 for transmitting UV light 306 through UV light tube 308.
As such, in the exemplary embodiment, UV light tube 308 is formed at
least partially from a transparent material that does not react with UV
light 306. It should be understood that UV contactor 304 may have any
suitable number and/or configuration for UV light tubes 308. In the
exemplary embodiment, UV contactor 304 includes an array of sour water
tubes 310 that are in flow communication with an inlet manifold 312.
Inlet manifold 312 is in flow communication with stripper cooler 90.
Although FIG. 5 illustrates that sour water tubes 310 are vertically
oriented, it should be understood that sour water tubes 310 may have any
suitable orientation and/or configuration that enables treatment unit 300
to function as described herein. In the exemplary embodiment, sour water
tube 310 is in flow communication with a liquid outlet line 314 that is
in flow communication with recycled solids tank 100 and/or condensate
stripper 80. Treatment unit 300 also includes at least an inlet valve 316
and an outlet valve 318 for use in controlling a flow of stripped sour
water 92 through UV contactor 304.

[0035]Control system 106 is in operational control communication with at
least valve 316, UV light generator 302, UV contactor 304, and valve 318
for controlling components of treatment unit 300 to function as described
herein. During a treatment operation, stripped sour water 92 enters UV
contactor 304 from stripper cooler 90 when valve 316 is opened. More
specifically, stripped sour water 92 is discharged from stripper cooler
90 into at least one sour water tube 310. Further, UV light generator 302
generates UV light 306 and transmits UV light 306 to UV contactor 304.
More specifically, UV light 306 is transmitted through at least one UV
light tube 308. When stripped sour water 92 flows through sour water
tubes 310, stripped sour water 92 flows past UV light tube 308. As
stripped sour water 92 flows past UV light tube 308, UV light 306 causes
contaminates within stripped sour water 92 to react such that
contaminates is substantially removed from stripped sour water 92 to
produce treated sour water 98. Treated sour water 98 is then channeled
through liquid outlet line 314 to recycled solids tank 100. Alternatively
or additionally, treated sour water 98 is channeled through liquid outlet
line 314 to condensate stripper 80.

[0037]Hydrogen peroxide contactor 404 includes, in the exemplary
embodiment, a sour water inlet 412, at least one nozzle 414, a treated
sour water outlet 416, and a safety valve 418. Sour water inlet 412 is
coupled in flow communication with stripper cooler 90, and treated sour
water outlet 416 is coupled in flow communication with a liquid outlet
line 420. Nozzle 414 is coupled in flow communication with hydrogen
peroxide storage tank 402. Safety valve 418 controls at least a pressure
within hydrogen peroxide contactor 404, and an outlet valve 422 is
coupled to liquid outlet line 420 to control a flow of treated sour water
98 through liquid outlet line 420. In the exemplary embodiment, hydrogen
peroxide contactor includes a plurality of nozzles 414 that are coupled
in flow communication with a manifold 424 that is in flow communication
with hydrogen peroxide storage tank 402.

[0039]In the exemplary embodiment, metering valve 405 and/or metering pump
406 channels hydrogen peroxide 408 to manifold 424 for discharge into
hydrogen peroxide contactor 404 through nozzles 414. When hydrogen
peroxide 408 contacts stripped sour water 92, hydrogen peroxide 408 and
stripped sour water 92 react to substantially remove contaminates from
stripped sour water 92 to produce treated sour water 98. In the exemplary
embodiment, hydrogen peroxide contactor 404 is designed with sufficient
residence time to perform a chemical reaction of the contaminates within
stripped sour water 92 to produce treated sour water 98. Treated sour
water 98 is channeled through liquid outlet line 420 to recycled solids
tank 100. Alternatively or additionally, treated sour water 98 is
channeled through liquid outlet line 420 to condensate stripper 80.

[0040]The embodiments described herein provide methods and systems for
removing contaminates from sour water before the sour water is channeled
to a storage tank and/or further processing units. As such, the
above-described embodiments facilitate reducing a possibility of
contaminates and/or other potentially volatile materials, such as
ammonia, cyanide, and/or organics, from being undesirably routed to a
recycled solids tank, which may lead to exposure to contaminates.
Further, the systems described herein facilitate reducing accumulation of
contaminates in a condensate ammonia stripper, which facilitates reducing
the need for more expensive materials to be used in the condensate
ammonia stripper systems, as compared to ammonia stripper systems having
contaminates therein.

[0041]Exemplary embodiments of methods and systems for treating sour water
are described above in detail. The methods and systems are not limited to
the specific embodiments described herein, but rather, components of
systems and/or steps of the methods may be utilized independently and
separately from other components and/or steps described herein. For
example, the methods may also be used in combination with other sour
water producing systems and methods, and are not limited to practice with
only the gasification systems and methods as described herein. Rather,
the exemplary embodiment can be implemented and utilized in connection
with many other contaminates removal applications.

[0042]Although specific features of various embodiments of the invention
may be shown in some drawings and not in others, this is for convenience
only. In accordance with the principles of the invention, any feature of
a drawing may be referenced and/or claimed in combination with any
feature of any other drawing.

[0043]This written description uses examples to disclose the invention,
including the best mode, and also to enable any person skilled in the art
to practice the invention, including making and using any devices or
systems and performing any incorporated methods. The patentable scope of
the invention is defined by the claims, and may include other examples
that occur to those skilled in the art. Such other examples are intended
to be within the scope of the claims if they have structural elements
that do not differ from the literal language of the claims, or if they
include equivalent structural elements with insubstantial differences
from the literal language of the claims.